= nbd-mount-helper
:wiki: https://en.wikipedia.org/wiki/Network_block_device

This project includes mount helpers for `nbd` and `nbdfuse` entries in
`/etc/fstab`. The helpers are `bash` scripts that should be installed
in `/sbin` to be ued by `mount` to handle the virtual filesystem types
`nbd` or `nbdfuse`. (Or installed in `/usr/sbin` for some versions of
`mount`)

== Description

Quoting                 
Wikipedia about
link:https://en.wikipedia.org/wiki/Network_block_device[Network Block Device]

[quote]

On Linux, network block device (NBD) is a network protocol that can be
used to forward a block device (typically a hard disk or partition)
from one machine to a second machine. As an example, a local machine
can access a hard disk drive that is attached to another computer.

To do so, a remote machine, say `nbdhost.example.com` is set up as
`NBD server` with one or more export names, say including `part000`,
that on the server side maps to a partition image or file.

With a mount helper the client side would include an entry in its
`/etc/fstab` for instance like the following:
----
nbd://nbdhost.example.com/part000 /nbd/1 nbd noauto,noatime 0 2
----
That would declare a mounting of that exported NBD partition onto the
(already existsing) pathname `/mnt/1` on the local machine. With the
__type__ field of the `fstab` entry being `nbd`, the mount program
will use `/sbin/mount.nbd` as helper for handling that entry.

The helper script `/sbin/mount.nbd` provided here uses the
`nbd-client` program to handle the service connection and provide that
as a device node such as `/dev/nbd0`. Ths script mounts that device
node on `/mnt/1` and spawn a monitor daemon to terminate the service
connection upon unmounting. This script needs `inotify`, `nbd-client`
and the `nbd` kernel module or built-in to function.

The helper script `/sbin/mount.nbdfuse` provided here is similar but
will rely on `nbdfuse` for service connection and presents that on a
`/run` directory (named by a mangling of the remote URL). For this
case the `fstab` entry would then have `nbdfuse` as __type__
indicator. The helper script mounts the `nbdfuse` "partition" on
`/mnt/1` and spawn a monitor daemon to terminate the service
connection upon unmounting. This script needs `inotify`, `nbdfuse` and
the `fuse` and `loop` kernel modules or built-in to function.